


In-depth study of the keyword matching project - the introduction of filters, in-depth study of filters
In-depth study of the keyword matching project (1) - the introduction of filters
When you start reading this article, please first understand the step-by-step instructions for how to do a keyword matching project (search engine) ---- Day 1 ~ The step-by-step guide to how to do a keyword matching project (search engine) ---- Day 1 Twenty-two days
Foreword
<p> 接上回说到,小帅帅把完成后的代码,以及测试结果给出来后,于老大也没多说什么,就被要求上线了,原因很简单:大家都想有点贡献,福利也是少不了的,后期遇到的事情后期再来升级,那餐饭,小帅帅很happy,很满足,当然同行的有小丁丁,于老大,王总监。</p>
Antecedents of the problem
With the operation of the project, the application of collecting keywords is becoming more and more widespread. Suddenly one day, Xiao Ding Ding came to find Xiao Shuai Shuai. Of course, Xiao Shuai Shuai was very happy, but after hearing the conversation that followed, he was greatly disappointed.
"Xiao Shuai Shuai, look, why do these words have &,?,%, there are a lot of messy words, these words are not suitable for use, please help me how to remove them." Little Ding Ding's eyes It was powerful enough, and it made Xiao Shuai Shuai tremble.
“Sister, okay, I’ll go take a look first, I’ll take care of this matter, and I’ll let you know when it’s resolved.”
Xiaoshuai went back to check and found that there were many such weird words in the database. Xiaoshuai panicked and had to find Boss Yu again.
“Now there are many words like &,?,% in the vocabulary keywords, and based on the matching algorithm, these words are all available. What should we do?”.
Boss Yu listened to Xiao Shuaishuai’s explanation and came up with a plan. Let’s control these keywords. Since these keywords are not used in the business anyway, we don’t want them to be included in the database. This can reduce the number of keywords. The amount of the library can also ensure high availability of keywords.
When Xiao Shuai Shuai heard it, he was different from the boss and couldn't catch up with him.
Solution
Add a function to control the source of the word into the library, meet the admission of the rules, and do not meet the discard of the rules-the function of the filter.
Design Plan
<p><strong> </strong> <img alt="In-depth study of keyword matching projects - introduction of filters, in-depth study of filters_PHP tutorial" ><span> 1</span> <span>class</span><span> Source { </span><span> 2</span> <span> 3</span> <span>public</span> <span>$keywords</span><span>; </span><span> 4</span> <span> 5</span> <span>public</span> <span>function</span><span> run() { </span><span> 6</span> <span> 7</span> <span>foreach</span> (<span>$this</span>->keywords <span>as</span> <span>$word</span><span>) { </span><span> 8</span> <span>#</span><span> code...</span> <span> 9</span> <span>if</span>(Filter::is(<span>$word</span>)) <span>continue</span><span>; </span><span>10</span> <span>11</span> <span>$keyword</span> = <span>new</span><span> Keyword(); </span><span>12</span> <span>$keyword</span>->word = <span>$word</span><span>; </span><span>13</span> <span>$keyword</span>-><span>save(); </span><span>14</span> <span> } </span><span>15</span> <span> } </span><span>16</span> <span>17</span> }
3. Add new Filter code:
<span> 1</span> <?<span>php </span><span> 2</span> <span> 3</span> <span>#</span><span>@Filename: filter/Filter.php</span> <span> 4</span> <span>#</span><span>@Author: oShine</span> <span> 5</span> <span> 6</span> <span>class</span><span> Filter { </span><span> 7</span> <span> 8</span> <span>private</span> <span>static</span> <span>$filterWords</span> = <span>array</span>("*","?","%",".","&"<span>); </span><span> 9</span> <span>10</span> <span>public</span> <span>static</span> <span>function</span> is(<span>$word</span><span>){ </span><span>11</span> <span>$pattern</span> = "/(".<span>implode</span>("|", self::<span>$filterWords</span>).")/"<span>; </span><span>12</span> <span>return</span> <span>preg_match</span>(pattern, <span>$word</span><span>); </span><span>13</span> <span> } </span><span>14</span> <span>15</span> }
Summary
Good code structure, adding and removing functions is very simple, and work efficiency is improved. Xiao Shuai Shuai fell deeply in love with this job.

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